Tread compound comprising trialkoxymercaptoalkyl-silanes

Abstract

A method of producing a rubber compound, including a first mixing step of mixing at least one cross-linkable unsaturated-chain polymer base, silica, and a silane coupling agent in the mercaptoalkyl-silane class; and a final mixing step, in which a curing system is added to the mix. The silane coupling agent is used in adsorbed form on dibenzothiazyl disulphide.

1 . A method of producing a rubber compound, comprising a first mixing step of mixing at least one cross-linkable unsaturated-chain polymer base, silica, and a silane coupling agent in the mercaptoalkyl-silane class; and a final mixing step, in which a curing system is added to the mix; said method being characterised in that said silane coupling agent is used in adsorbed form on dibenzothiazyl disulphide. 
     
     
         2 . A method of producing a rubber compound, as claimed in  claim 1 , characterized in that, at said first mixing step, the mix comprises 10 to 100 phr of silica with a superficial area of 170 to 230 m 2 /g. 
     
     
         3 . A method of producing a rubber compound, as claimed in  claim 2 , characterized in that, at said first mixing step, the mix comprises 1 to 20 phr of a silane coupling agent in the trialkoxymercaptoalkyl-silane class. 
     
     
         4 . A method of producing a rubber compound, as claimed in  claim 1 , characterized in that said silane coupling agent is used in adsorbed form on 0.5 to 6 phr of said dibenzothiazyl disulphide. 
     
     
         5 . A method of producing a rubber compound, as claimed in  claim 1 , characterized in that said silane coupling agent is also used in adsorbed form on 5 to 10 phr of carbon black. 
     
     
         6 . A method of producing a rubber compound, as claimed in  claim 1 , characterized in that said silane coupling agent has the formula (I)
   R 1 R 2   2 Si—R 3 —SH   (I)
   where:   R 1  represents a linear, cyclic or branched alkoxyl group with 1 to 8 carbon atoms; R 2  represents a linear, cyclic or branched alkoxyl group with 1 to 8 carbon atoms, or —O—(Y—O)m4-X (where Y represents a linear, cyclic or branched saturated or unsaturated divalent hydrocarbon group with 1 to 20 carbon atoms, X represents a linear, cyclic or branched alkyl group with 1 to 9 carbon atoms, and m4 represents a number of 1 to 40); and R 3  represents a linear, cyclic or branched saturated or unsaturated alkylene group with 1 to 12 carbon atoms.   
     
     
         7 . A method of producing a rubber compound, as claimed in  claim 6 , characterized in that said silane coupling agent is in the trialkoxymercaptopropyl-silane class. 
     
     
         8 . A method of producing a rubber compound, as claimed in  claim 7 , characterized in that said silane coupling agent has the formula (II)
   SH(CH 2 ) 3 SiR 4 R 5   2    (II)
   where:   R 4  is —OCH 2 CH 3 , and   R 5  is —O(CH 2 CH 2 O) 5 (CH 2 ) 13 CH 3      
     
     
         9 . A tread compound, characterized by being produced using the method as claimed in  claim 1 . 
     
     
         10 . A tread, characterized by being produced from the compound as claimed in  claim 9 . 
     
     
         11 . A tyre comprising a tread as claimed in  claim 10 .